Are JFETs biased differently from standard bipolar transistors? Them must be, or the schematic I have is crap. The gate/drain junction is not biased with reverse polarity, like I am used to with, say, 2N3904s. It looks like it is forward based just like the source/gate junction. Any words of wisdom are welcome. Obvious newbie here...
Thanks,
Dave
Don't assume that the two are mutually exclusive. It could be that JFETs are biased differently from bipolars (they are) *and* the schematic you have is crap.
I hope this helps. :)
If the gate is a higher voltage than the drain (assuming the schematic isn't crap) check to see if the JFET is P-channel (analogous to a PNP bipolar).
Generally a JFET will conduct serious current when the gate-source voltage is zero, so you will often see N-channel JFETs biased with a DC path to the negative rail and the source connected to the same rail through a small resistor.
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